Wrapping machine



March .25, 1939.

M. KRAFFT Y WRAPPING MACHINE Filed Aug.

24. 1957 5 Sheets-Sheet l March 28, 1939.y M KRAFFT WRAPPNG MACHINE 5 sheets-sheet 3 Filed Aug. 24. 1937v March 28, 1939.

M. KRFFT WRAPPING MACHINE Filed Aug. 24, 1937 5 Sheets-Sheet 4 b777. Kay??? Marh2s,1939.' MKRAFFT 2,152,142

WRAPPING MACHINE l Filed Allg. 24, 1937 5 Sheets-Sheet, 5.

Patented Mar. 28, 1939 PATENT OFFICE 2,152,142 WRAPPING imicHINr:k

Maurice Kraift, Lausanne, to the firm Sapal Socit Automatiques, Lausanne,

vApplication August 24, 1937,

In Switzerland September 1,

5 Claims.

The present invention relates to wrapping-machines for wrapping articles the transverse sectional area of which varies over the length of the article, such as for instance `sweet meats, chocolates, de luxe bonbons and like articles. Heretofore articles of this kind havebeen usually wrapped by hand owing Ito their particular shape and the required high quality of wrapping.

It is an -object of 'the present invention to replace this manual work by automatic operations performed on a wrapping machine whereby, at the same time, the required amount of wrapping material is 'limited to a minimum.

Machines for wrapping articles having a varying transverse sectional area over their length are already known in which folding tools apply a sheet of wrapping material around the article in such manner'that the sheet fis shaped to a straight tube which is tangential to the article along the periphery of that Vtransverse sectional area thereof which has the lgreatest diameter.

According :to the vpresent invention the wrapping is effected at a plurality of stations at each of which one wrapping tool at least is arranged `to be approached to and removed Vfrom the article, to apply the tube-shaped wrapping sheet against those portions of the article 'having a 'smaller diameter than the `tube-shaped sheet, and a plurality of cam controlled gripping devices provided with clamping jaws are arranged to simultaneously engage the articles situated at the various stations, to be displaced in a direction substantially parallel to the opening and closing movement ofthe jaws for bringing each article to the next following station, to be opened and removed from the articles in a direction at right angles to the direction'of movement of the clamping jaws, to be returned to the preceding stations in a direction parallel to the movement of the clamping jaws, and again to approach the articles for engaging each a new article. The working surface of thetools which adapt the tube shaped wrapping sheet on vthe article preferably forms a negative of the surface portion of the article against whichthe sheet is applied, so that these tools effect a wrapping operation while gripping an article at one of the operating stations and transporting it to the following station.

The accompanying drawings illustrate a preferred example of a wrapping machine according to the invention.

Figure 1 shows in diagrammatic manner a plan view of apart of the wrapping machine.

Figure 2 is an elevation thereof.

Figures 3 and-4 show a plan View and an eleva- Switzerland, `assignor Anonyme des Plieuses Switzerland Serial No. 160,667 1936 tion, respectively, of the machine in another phase of operation, and Figures 5 and 6 are similar views of the machine in a third phase of operation.

Figure '7 shows a detail in section drawn to a 5 larger scale.

Figure 8 is a section along'the line 8-8 of Fig. 1.

Figs. 9, 10 and 1l show each a cam actuated control device of three :different movable members of the wrapping machine.

In Figs. 1 and 2 the article 3 to be wrapped is brought by conveying members, not shown, to a vertically movable carrier I. This carrier is slidably mounted in a vfixed guide member 52 and is connected to one end fof a lever l53 rotatably 15 mounted on a rod Ml, while the other end of the lever carries a cam follower 54 urged against a cam 55, secured to a shaft 56 (Fig. 9) ,by a spring/ 14. A sheet of wrapping material 2, as for example a sheet of aluminium foil, is delivered in any known manner upon the article 3. A vertically movable plunger la is slidably mounted on a guide 'member 5l and connected to one end of a'lever 58 rotatably mounted on the rod 40, while the other end of the lever carries a cam follower 59 urged against a cam 50, secured `to the shaft 56 (Fig. 10), by a spring 15. This plunger la is lowered on the wrapping sheet Zand the article 3. The carrier l and plunger la theneffect a simultaneous upward movement to the level of a horizontal table 5. The article with the wrapping sheet `2 is thus drawn across folding members 4 and la which fold the sheet downwards (Fig. 4) .so that it obtains the shape of a reversed U.

The folding member 4a is adjustable in horizontal direction, so as to passbeneath the article in order to effect a folding operation as will be described hereinafter. For this purpose, the folding member 4a is mounted at one end of a lever 'l rotatably mounted at 62 on the frame of the machine, and the other end of the lever is connected to a rod 63 in turn connected to a lever 164 which is pivotally mounted at 65. This lever 64 carries a cam follower 65 urged against a cam 6-1, secured to alshaft 68, Vby means of a spring 16. The rst operation of the wrapping is now flnished and the place at which this operation has been effected will be designated by station A. The previously arrived articles are now situated on the various stations B, C, D on the table 5.

Above the table 5 is disposed a double guide rail (i, situated in a plane parallel to the table 5, and' carrying two independently movable slides 'I and 8, the rst one rbeing disposed along the upper 6l face, and the second along the lower face of the rail I5, and both slides being connected to control cams 30 and 3l by the intermediary of the rods lf3 and I5 and the levers 32 and 33, rotatably mounted at 34 and 35, respectively, and carrying cam followers 36 and 3'I.

A vertical guide rail 9, rigid with the frame of the machine, carries a slide I to which is secured an arm I I extending parallel with the guide rail 6. This latter rail 6 is movable in a transverse direction relative to the table 5, and is carried by a slide 2! movable along a guide I9. The slide I0 is controlled by a lever Il movable about the axis I8, and the slide 2D is moved by a rod 2l. The lever Il is connected by means of a rod 38 to a lever 35 rotatably mounted at 40 and carrying a follower 4I applied against a cam` 42. The rod 2I is connected to a lever 44 rotatably mounted at 25 and carrying a follower 46 held in Contact with a cam 41.

Three gripping and conveying members cornprise each a pair of clamping jaws 22, 23 and 24, respectively. The right hand jaws of each pair are secured to the upper slide 1, and the left hand jaws to' the lower slide 8; The three clamps accordingly open and close together. The various cams control the movement of the gripping members in such manner, that when the three pairs of jaws are open, they can be moved backwards by the slide 2Q (Fig. 3), then the rods I4 and I5 move them towards the left, and the slide 2l) again moves them forwards; afterwards the rods I4 and I move relatively to each other to simultaneously close the three pairs of clamps on'the articles situated at the various stations (Fig. 5), and finally the three gripping members move simultaneously towards the right to bring the articles to the next following stations.

The jaws 22 and 24 are provided with plane clamping faces which may be coated with a soft material, while the jaws 23 have a working surface which forms a negative of the surface portion of the article engaged by these jaws.

The arm II carries two slidable plungers I2 and I3 subjected to the action of springs which push the plungers downwardly. The plunger I2 is situated above the station B and is provided with a contacting face which may be applied on the article to maintain the latter at the station, when the gripping members are removed from the article. At this station B acts a folding tool 25 which is vertically movable and can penetrate through an opening in the table 5, in order to apply'the front and rear ends of the sheet'2 against the article. The tool 25 is slidably mounted in a guide 69 and is connected to one end of a lever 'IIJ rotatably mounted on the rod 4I), while the other end of the lever carries a cam follower 'II urged against a cam 72, also secured to the shaft 56, by means of a spring 'I8 (Fig. l1) Y The plunger I3 is provided with a contacting surface 25 forming aV negative of the surface portion of the article against which the plungeris applied. V The plunger I3 is hollow and traversed by a spindle 27 which is movable relative to the plunger and also urged downwardly by a spring 28.

The plunger i3 traverses the arm I I and is secured to a rod 49 to which is attached one end of a spring 50 having its other end connected to the arm II. The rod 49 is guided in a fork 5I. When the arm YI I moves downwardly, the surface 26 forming a mold, is applied on an article, and while the arm II continues to move, the plunger I3 is raised relatively to the arm and tensions the Vbe wrapped.V

spring 5U which thus yieldingly urges the mold against the article.

The spindle 2l maintains the article in its position'when the jaws 23 or 24 open and the mold 26 is applied to or removed from the article.

'Ihe cams which control the movements of the described folding tools and other movable members are disposed in two groups. The cams 42, li?, 55, BIJ and 72 are mounted on a shaft 56, while the cams 30, 3l and 6l are,` mounted on a shaft 58. The two shafts areV connected to each other by means of gears 'I3 so that they rotate in synchronism.V The shaft 68 may be connected to any convenient power source, not shown.

The article to be wrapped and represented by way of example has the shape of a miniature bottlerhaving a bulbed side and a flat side, which shape, until now, required to be wrapped by hand, or, whenY using a wrapping device with wiper members, requiredl an unusually large amount of wrapping material. V

The operation-of the machine will be readily Yunderstood from the following description of the passage through the machine of an article 3 to In Fig. 2 an article 3 is disposed on the carrier I, a sheet of wrapping material 2 is laid on the article and the plunger Ia'lowered to hold the sheet in position on the article. Raising of the carrier I and plunger Ia brings the article on the level of the table 5 while passing between the folding members 4 and 4a which fold the sheet downwards about the article'as shown in Fig. 4. 'Ihese operations are performed at the station A.

The jaws 22, 23 and 24 are then in the position shown in Fig. 3. They are now moved towards the left, so that the jaws 22 arrive behind -the station A, and then all the jaws are moving forwards and are closed, to arrive in the position shown in Figs. 5 and 6, the jaws 22 having gripped the article 3 situated at the station A. At this moment the carrier VI and plunger Ia are retracted, towards below and towards above, respectively, and the movable folding member 4a "moves towards the right beneath the article to fold 'the left side of the wrapping sheet 2 against the bottom face of the article (Fig. 6). All the -jaws are now moved towards the right, so that the jaws 22 bring the article 3 to the station B.

-While the article passes over the edge of the table 5 carrying the folding member 4, the right side of the wrapping sheet 2 is also applied towards the bottom face of the article, so that when the article arrives at the station B, the sheet 2 is wrapped around the article in the shape of a Vstraight tube whichY is tangential to the article alongV that circumference having the greatest diameter. The arm II is. then Ylowered to apply the plunger. I2 against the article, the jaws 22, as also the jaws 23 and 24, are opened and retracted from the article, While the folding tool 25 is raised and passes across the opening in the table 5 to apply the front and rear ends of the sheet 2 against the article. The tube-shaped wrapping sheet has thus received its first deformation.A The jaws now move towards the left again and then forwards, so that the jaws 23 grip the article at the station B, while the jaws 22 grip a new article at the station A. The holding plunger I2 is now raised and the jaws moved towards the right so that the article gripped at the station B is moved to the station C. During this transfer of the article to the station C the jaws 23, the clamping surfaces of which correspond to the shape `of thearticle, apply the lateral portions of the tube-shaped wrapping sheet against the surface of lthe article. At this station thefspindle 21 iis Ilowered on the .article to hold the .same in place while the jaws are retracted. The plunger -26 is fnow lowered and applies vthe upper portion of .the wrappingvsheet towards the surface of the Iarticle. The wrapping .of the article is now completed. vThe jaws are again moved towards the left-and then advanced, so that the jaws 24 grip the article at the station C after the .plunger 26 has vbeen raised. Then the spindle 21 is also raised and the jaws moved towards the right to carry the article to the station D on a conveyer band I6 which removes the completely wrapped article from the machine.

It will be understood that the number of the stations can be smaller or greater, according to the shape of the article to be wrapped. Also, the wrapping members could move along inclined planes instead of moving horizontally or vertically, and the clamping jaws could effect a movement of rotation instead of moving rectilinearly in a plane.

An advantage of the described machine is realized by the fact that articles of nonprismatic shape can be completely wrapped by first rolling the wrapping material to the shape of a straight tube around the article, this rolling operation being the base of every high quality wrapping, as it is also made when wrapping articles by hand, and permitting the use of a sheet of minimum size.

I claim:

1. In a wrapping machine for wrapping articles having transverse sectional areas of varying diameter, a plurality of operating stations at which the wrapping is effected, means operable at the rst of said stations for folding a sheet of Wrapping material around the article to the shape of a straight tube disposed tangential to the article along the circumference of that transverse sec tional area thereof having the greatest diameter, and a plurality of grippers for moving the articles from one operating station to the next following station, one at least of said grippers having gripping surfaces of a shape corresponding to a portion of the shape of the articles to be Wrapped whereby said gripper, upon gripping an article partially wrapped in said tube-shaped wrapping sheet to carry the article from one sta tion to the next following station, simultaneously performs a wrapping operation/ by applying a portion of the tube-shaped wrapping sheet against that surface portion of the article corresponding to the shape of the gripping surfaces.

2; In a wrapping machine for wrapping articles having transverse sectional areas of varying diameterga plurality of operating stations at which the wrapping is effected, means operable at the rst of said stations for folding a sheet of wrapping material around the article to the shape of a straight tube disposed tangential to the article along the circumference of that transverse section thereof having the greatest diameter, a plurality of grippers for moving the articles from each operating station to the next succeeding station, said grippers being operable to grip an article at one station, to transfer the article to the next succeeding station and then to return to the preceding station, and holding means operable in timed relationship with said grippers to hold the articles at the operating stations when not engaged by the grippers, one of said grippers having gripping surfaces forming a negative of a portion of the surface of the article to be wrapped whereby said gripper, upon gripping an article vpartially wrapped in said tube-shaped Vsheet to ytransfer the article to the next succeeding station, simultaneously performs a Wrapping operation by applying a portion of the tubeshaped wrapping sheet towards the surface .of the article.

3. In a wrapping machine for wrapping articles having transverse sectional areas of varying di- .ameter, ,a plurality of stations at which the wrapping operations are successively effected, .means operable at the rst of said stations for folding a sheet of wrapping material around the article to the shape of a straight tube disposed tangential to the article along the circumference of that transverse section thereof having the largest diameter, a plurality of grippers for moving the articles from each operating station to the next succeeding station, one of said grippers having gripping surfaces forming a negative of a portion of the surface of the article to be wrapped whereby said gripper, upon gripping an article partially wrapped in ysaid tube-shaped sheet to transfer the article to the next succeeding station, simultaneously performs a wrapping operation by applying a portion of the tube-shaped sheet towards the surface of the article, and a plunger actuated Wrapping tool operable at the station to which said lgripper transfers the article to be wrapped, said wrapping tool having a surface forming a negative of another surface portion of the article for applying the tube-shaped wrapping sheet to a portion of the surface of the article not acted upon by said gripper.

4. In a wrapping machine for wrapping articles having transverse sectional areas of varying diameter, a plurality of stations at which the wrapping operations are successively effected, means operable at the rst of said stations for folding a sheet of wrapping material around the article to the shape of a straight tube disposed tangential to the circumference of that transverse section of the article having the largest diameter, a plurality of grippers for moving the articles from each operating station to the next succeeding station, one of said grippers having gripping surfaces forming a negative of those portions of the surface of the article engaged by the gripping surfaces whereby said gripper, when gripping the article partially wrapped in said tube-shape wrapping sheet for carrying the article from one station to the next succeeding station applies a portion of the tube-shaped wrapping sheet towards the surface portions of the article engaged by the gripper, a wrapping tool operable at that station to which said gripper carries the partially wrapped article, a hollow plunger carrying said tool, means operable in timed relationship with the grippers for reciprocating said plunger and tool towards and away from said partially wrapped article in a direction perpendicular to the plane of movement of the grippers, and a resilient holding spindle slidable within said hollow plunger and adapted to hold said article in position when released by the gripper.

5. In a wrapping machine for wrapping articles having transverse sectional areas of varying diameter, a plurality of stations at which the wrapping operations are successively effected, means operable at the first of said stations for folding a sheet of wrapping material around the article to the shape of a straight tube disposed tangential to the circumference of that transverse section of the article having the largest diameter, a plurality of grippers for moving the articles from each operating station to the next succeeding station, each of said grippers including a pair of clamping jaws, a reciprocable slide carrying one of the jaws of each pair of jaws, a second reciprocable slide carrying the second jaw of each pair of jaws, cam means controlling the movement of the slides and operable to cause the slides to move together for reciprocating the grippers between succeeding stations and to cause the slides to move in opposition to each other for opening and closing the jaws, means for moving said slides in' a direction perpendicular to the movement imparted by said cam means for removing the grippers from and approaching them towards the'articles at said stations, one of said grippers having gripping surfaces forming a negative of those surface portions of the article engaged by the gripper whereby said gripper, upon gripping and transporting the article partially wrapped in said tube-shaped sheet applies a portion of the sheet towards the surface portions of 10 the article engaged by the gripper.

' MAURICE KRAFFT. 

